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3 years ago

How do you know how many valence electrons are in a molecule?

Chemistry

2 answers:

telo118 [61]3 years ago

4 0

1. by making a atomic configuration
2.by making a table of shells of k.l.m.n....
that's all

Leno4ka [110]3 years ago

4 0

To know the number of valence electrons you must know the number of electrons in the outer shell .. In the periodic table there are 8 groups (which are the vertical columns) .. ignore the yellow ones for now which are the transition metals .. the group number is the number of electrons in the most outer shell of an atom .. so for example lithium and sodium are in group 1 so they have only 1 electron in their outer shell .. the valence electrons are the ones an atom looses or gains during a chemical reaction (atoms try to be stable by having 8 electrons in their outer most shell) .. for example atoms in group 1 have 1 electron in their outer shell that they want to loose so the valency is 1 .. In group 5 they need to become 8 so they gain 3 electrons so the valency is 3

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You have an unknown quantity of oxygen at a pressure of 2.2 atam, a volume of 21 liters and a temperature of 87 Celsius. How man

laila [671]

Let's assume that the oxygen gas has ideal gas behavior.
Then we can use ideal gas formula,
PV = nRT

Where, P is the pressure of the gas (Pa), V is the volume of the gas (m³), n is the number of moles of gas (mol), R is the universal gas constant ( 8.314 J mol⁻¹ K⁻¹) and T is temperature in Kelvin.

P = 2.2 atm = 222915 Pa
V = 21 L = 21 x 10⁻³ m³

n = ?

R = 8.314 J mol⁻¹ K⁻¹

T = 87 °C = 360 K

By substitution,
222915 Pa x 21 x 10⁻³ m³ = n x 8.314 J mol⁻¹ K⁻¹ x 360 K
n = 1.56 mol

Hence, 1.56 moles of the oxygen gas are left for you to breath.

6 0

3 years ago

Need help balancing equations please.

densk [106]

Answer:

A, 4,3,2

B, 1,1,2

C, 1,1,1,2

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2 years ago

Atom with three full orbits What is it

nekit [7.7K]

Answer:

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3 years ago

Read 2 more answers

What is the sequence of coefficients that will balance the following decomposition reaction of dihydrogen monosulfide? H₂S ----&

RUDIKE [14]

8 S

In this case you must start balancing the sulfur to have 8 on each side of the reaction. So:

Answer:

Explanation:

The law of conservation of matter states that since no atom can be created or destroyed in a chemical reaction, the number of atoms that are present in the reagents has to be equal to the number of atoms present in the products.

Then, you must balance the chemical equation. For that, you must first look at the subscripts next to each atom to find the number of atoms in the equation. If the same atom appears in more than one molecule, you must add its amounts.

The coefficients located in front of each molecule indicate the amount of each molecule for the reaction. This coefficient can be modified to balance the equation, just as you should never alter the subscripts.

By multiplying the coefficient mentioned by the subscript, you get the amount of each element present in the reaction.

Then, taking into account all of the above, you can determine the amount of elements on each side of the equation:

Left side: 2 H and 1 S

Right side: 2 H and 8 S

In this case you must start balancing the sulfur to have 8 on each side of the reaction. So:

8 H₂S → H₂ + S₈

Now the amount of elements on each side of the equation:

Left side: 16 H and 8

Right side: 2 H and 8 S

Now you need to start balancing the hydrogen to get the same amount from each side of the reaction. So:

8 H₂S → 8 H₂ + S₈

Now the amount of elements on each side of the equation:

Left side: 16 H and 8

Right side: 16 H and 8 S

The balanced reaction is:

8 H₂S → 8 H₂ + S₈

3 0

2 years ago

Pls help it’s due tomorrow morning need you help as soon as possible!! ;) ❤️ Thanks

IrinaVladis [17]

Answer:

I have solved your problem

Explanation:

6 0

3 years ago